1. Field of the Invention
The present invention relates to an imaging apparatus, and, more particularly, to an apparatus and method for calibrating a printhead.
2. Description of the Related Art
In ink-jet printer systems, calibrations are required in order to ensure that the ejected drops of ink land at the desired location on the print medium. In one aspect of calibration, it is desirable that the appropriate amount of energy is used in order to eject the ink drops. The use of too little firing energy may result in variations in the amount and location of the ejected ink drops, resulting in unacceptable printed results. Too much firing energy may result in a reduced life of the printhead. The ink drop velocity can vary due to differences in the printhead, for example, different heater chip resistances or piezo electric crystal characteristics, changes in voltage level of power supply, and ink chemistry.
In addition, in order to perform bi-directional printing, e.g., printing while the printhead is moving across the page in a first direction and also printing as it is moving back in the opposite direction, it is necessary to compensate for the different printing directions so that the ink is deposited in the desired location.
What is needed in the art is an apparatus and method for calibrating a printhead.